The
Ramsar Convention on Wetlands
The
Ramsar Convention on Wetlands
The Ramsar Convention's resources on Wetland Restoration
The STRP Expert Working Group on Wetland Restoration
Wetland Restoration Glossary
| The jargon associated with
wetland restoration can be a source of confusion. Although different people use the same
terms or phrases, the intended meaning of the terms or phrases can be very different. For
example, Louda (1988) defines "ecological restoration" as an acceleration of the
reestablishment of balanced plant communities, while Kauffman et al. (1997) use the same
phrase to represent a more complex idea that includes reestablishment of processes and
linkages between aquatic and riparian ecosystems. This glossary presents a collection of terms and phrases, along with their definitions. The purpose of this collection is to promote consideration of the many possible meanings of terms and phrases related to wetland restoration, with the hope that serious consideration of the many meanings of these terms and phrases will lead to improved communication among wetland professionals involved with restoration. For most of the terms or phrases presented, more than one definition is offered; when this is the case, the various definitions have been arranged subjectively from simplest to most complex. Whenever possible, direct quotes have been used, but in some cases information has been paraphrased. No attempt has been made to defend or advocate any of the definitions presented in this glossary. Definitions evolve with usage, and because of this evolution there is no objective manner in which definitions can be assessed. However, notes provide comments on current trends in usage, wherever this is appropriate. |
Definitions
Constructed wetlands
Constructed wetlands are "wetlands intentionally created from non-wetland sites for the sole purpose of wastewater or stormwater treatment" (Hammer 1997).
In the United States, the distinction between created wetlands and constructed wetlands appears to have become widely accepted over the past decade, but the older literature in the United States and literature from abroad may not distinguish between these terms.
Creation
Wetland creation is "the construction of wetlands where they did not exist before and can involve engineering of hydrology and soils" (Mitsch and Gosselink 1993).
"[Wetland creation is] establishing an ecosystem that did not originally occupy the site" (Middleton 1999).
"[Creation is the bringing] into being a new ecosystem that previously did not exist on the site" (National Research Council 1992).
"[Wetland creation is] the establishment of a wetland where no wetland had existed in the past" (Streever 1999).
"[Creation refers] to attempts to construct a wetland in an area that never has contained a wetland" (Kentula et al. 1993).
"[Creation refers to the] conversion of a persistent non-wetland area into a wetland through some activity of man" (Lewis 1990).
Note that this definition and the following two definitions refer to non-wetland areas, which might include mined lands or other areas where wetlands had been destroyed, while previous definitions of creation referred to sites that were never wetlands.
"[Created wetlands are] wetlands intentionally created from non-wetland sites to produce or replace natural habitat" (Hammer 1997).
"[Creation is the simulation] of natural wetland features and functions by topographic and hydraulic modification of nonwetland landscapes. Typical objectives of artificial marsh creation include ecosystem replacement or storm water management" (National Research Council 1992).
Unlike other definitions of wetland creation presented here, this definition suggests that creation can include wetlands intended for water quality improvement or water quantity management (storm water management). See "constructed wetlands" definition and the first note above.
Designer wetland
"[The concept of a designer wetland emphasizes] the life history strategy of species as the important factor in developing vegetation on a restoration site. The view favors engineering and replanting strategies directed at producing a wetland type with no fixed endpoint" (Middleton 1999).
In contrast, see the definition of "self-design."
Enhancement
"[Enhancement is] improving the structure or function of an already existing wetland" (Middleton 1999).
Obviously, "improvement" is a subjective term.
"In the context of restoration ecology, [enhancement is] any improvement of a structural or functional attribute" (National Research Council 1992).
"[Enhancement is the] increase in one or more values of all or a portion of an existing wetland by man’s activities, often with the accompanying decline in other wetland values" (Lewis 1990).
Mitigation
"[Mitigation is] the actual restoration, creation, or enhancement of wetlands to compensate for permitted wetland losses" (Lewis 1990).
This definition and the following definition of mitigation are not in agreement with the 1990 Department of the Army/Environmental Protection Agency Memorandum of Agreement.
"[Wetland mitigation is the replacing of] wetland areas destroyed or impacted by proposed land disturbances with artificially created wetland areas" (National Research Council 1992).
"The Council on Environmental Quality (CEQ) has defined mitigation in its regulations at 40 CFR 1508.20 to include: avoiding impacts, minimizing impacts, rectifying impacts, reducing impacts over time, and compensating for impacts" (Department of the Army and The Environmental Protection Agency 1990).
"[Mitigation is actions] taken to avoid, reduce, or compensate for the effects of environmental damage. Among the broad spectrum of possible actions are those that restore, enhance, create, or replace damaged ecosystems" (National Research Council 1992).
This definition of mitigation seems to be based on the 1990 US Army Corps of Engineers/Environmental Protection Agency Memorandum of Agreement, described in the previous definition.
Reclamation
"[Ecological restoration as reclamation is] any deliberate attempt to return a damaged ecosystem to some kind of productive use or socially acceptable condition short of restoration" (Jordan et al. 1988).
The term "reclamation" is itself used in at least three ways, referring to 1) conversion of mined or other disturbed lands into economically productive properties, such as grazing land or orchards, 2) filling in of wetlands or shallow coastal waters to create land, usually for housing or urban infrastructure, but also for agriculture in some parts of the world, and 3) conversion of disturbed lands to natural or semi-natural habitat. Because of dramatic differences in possible meanings, use of the term should probably be avoided.
"[Reclamation is] an alteration in an ecosystem that creates another type of ecosystem of value to humans" (Middleton 1999).
Reclamation is a "process designed to adapt a wild or natural resource to serve a utilitarian human purpose. Putting a natural resource to a new or altered use. Often used to refer to processes that destroy native ecosystems and convert them to agricultural or urban uses" (National Research Council 1992).
Reforestation
"[In reforestation,] specific components (e.g., trees) are restored such that structural replication of the previous ecosystem is achieved; with an implicit assumption the restoration will succeed reforestation" (Wilson et al. in press).
Terms such as "reforestation" and "revegetation" are sometimes applied to situations in which vegetation has not been previously established on the substrate in question, such as mine overburden sites, but many wetland professionals prefer terms such as "forestation" and "vegetation" in these situations, to avoid implying that vegetation had been present in the past.
Objectives of reforestation include 1) using native species to restore forested habitat, 2) creating habitat for the promotion of biodiversity, 3) developing habitat for wildlife, especially endangered species, and 4) producing a sustainable timber harvest (Strader et al. 1994).
Rehabilitation
"[Rehabilitation can be used as] an umbrella term that includes both ‘restoration’ and ‘creation’" (Streever 1999).
"[Rehabilitation is used] primarily to indicate improvements of a visual nature to a natural resource; putting back into good condition or working order" (National Research Council 1992).
Restoration
"[Restoration is the] return of a system to some previous condition" (Streever 1999).
"[Restoration is the return of a] damaged system to predisturbance condition[s]" (Cairns 1990).
Of course, it can be difficult to agree on what is meant by "predisturbance," since human disturbance of one kind or another has occurred throughout most of the world since the late Pleistocene.
"[Restoration is] any manipulation of a site that contains or has contained a wetland" (Kentula et al. 1993).
Restoration is the process of intentionally altering a site to establish a defined indigenous historic ecosystem (Aronson et al. 1993).
Restoration requires recreating both the structural and functional attributes of a damaged ecosystem (Cairns 1991).
"[To return an area from] a disturbed or totally altered condition to a previously existing natural, or altered condition by some action of man. Restoration refers to the return to a pre-existing condition" (Lewis 1990).
"[Restoration is] returning a site to approximately its condition before alteration, including its predisturbance function and related physical, chemical, and biological characteristics; full restoration is the complete return of a site to its original state" (Middleton 1999).
"[Restoration is the] return of an ecosystem to a close approximation of its condition prior to disturbance . . . [through] reconstruction of antecedent physical hydrologic and morphologic conditions; chemical cleanup or adjustment of the environment; and biological manipulation including revegetation and the reintroduction of absent or currently nonviable native species." Paraphrasing further information, restoration involves repair of ecological damage, as well as recreation of structure and functions, all with the goal of emulating "a natural, functioning, self-regulating system that is integrated with the ecological landscape in which it occurs" (National Research Council 1992).
Obviously, terms such as "functioning," "self-regulating," and even "natural" are subject to interpretation and contribute little to clarifying the definition of "restoration."
"[Restoration is] measures undertaken to return the existing fish and wildlife habitat resources to a modern historic condition. Restoration then includes mitigation as well as some increments of enhancement" (U. S. Environmental Protection Agency 1990).
This definition refers to a "modern historic condition," apparently in an attempt to recognize the difficulty of restoring systems to a condition typical of the distant past; i.e., it recognizes that it would be difficult to restore systems to, for example, precolumbian conditions.
"Restored wetlands are areas that previously supported a natural wetland ecosystem but were modified or changed, eliminating typical flora and fauna and used for other purposes but then subsequently altered to return poorly drained soils and wetland flora and fauna to enhance life support, flood control, recreational, educational, or other functional values" (Hammer 1997).
"[The ultimate goal of ecological restoration is perhaps] the achieving of a status something very close to the ecosystem’s original conditions" (Hamilton 1990).
"[Wetland restoration is] the rehabilitation of wetlands that may be degraded or hydrologically altered and often involves reestablishing the vegetation" (Mitsch and Gosselink 1993).
In contrast to previous definitions of restoration, this definition and the restoration definitions that follow it are less dependent on the concept of returning a system to past conditions.
"[Restoration is] recreation of entire communities of organisms, closely modeled on those occurring naturally" (Jordan et al. 1988).
Ecological restoration is the acceleration of "the reestablishment of natural plant communities" (Louda 1988).
Ecological restoration is long-term maintenance and management to ensure integrity, stability, and natural beauty (Guinon and Allen 1990).
"[Restoration is] the reestablishment of processes, functions, and related biological, chemical, and physical linkages between the aquatic and associated riparian ecosystems; it is the repairing of damage caused by human activities" (Kauffman et al. 1997).
"[Restoration is] the process of repairing damage caused by humans to the diversity and dynamics of indigenous ecosystems" (Jackson et al. 1995).
Riparian Reforestation
"[Riparian reforestation is the replanting] of the banks and floodplains of a stream with native forest and shrub species to stabilize erodible soil, improve both surface and ground water quality, increase stream shading, and enhance wildlife habitat" (National Research Council 1992).
Self-design
[Self-design is] "the idea that over time a restored wetland will organize itself around and eventually alter its engineered components…it is the environmental conditions there that determine the vegetative outcome" (Middleton 1999).
In contrast, see the definition for "designer wetlands."
References
Aronson, J. C., R. V. O’Neill, and R. W. Hoekstra. 1984. Interlevel relations in ecological research and management: Some working principles from hierarchy theory. USDA Forest Service General Tech Report RM-110. Rocky Mountain Forest and Range Experiment Station, Fort Collins, Colorado.
Cairns, J., Jr. 1990. The prediction, validation, monitoring and mitigation of anthropogenic effects on natural systems. Environmental Auditor 2:19-25.
Cairns, J., Jr. 1991. The status of the theoretical and applied science of restoration ecology. The Environmental Professional 13:186-194.
Department of the Army and The Environmental Protection Agency. 1990. Memorandum of Agreement between The Department of the Army and The Environmental Protection Agency concerning The Determination of Mitigation under the Clean Water Act Section 404(b)(1) Guidelines. (http://www.epa.gov/OWOW/wetlands/regs/mitigate.html)
Guinon, M. and D. Allen. 1990. Restoration of dune habitat at Spanish Bay. Pages 31-33 in W. R. Jordan, III, M. E. Gilpin and J. D. Aber (eds.), Restoration Ecology. Cambridge University Press, Cambridge, UK.
Hamilton, L. S. 1990. Restoration of degraded tropical forests. Pages 113-123 in J. J. Berger (ed.), Environmental restoration: Science for Restoring the Earth. Island Press, Washington, D. C.
Hammer, D. A. 1997. Creating Freshwater Wetlands, 2nd ed. Lewis Publishers, Inc., Boca Raton, Florida.
Jackson, L. L., N. Loupoukhine, and D. Hillyard. 1995. Commentary; Ecological restoration: A definition and comments. Restoration Ecology 3:71-75.
Jordan, W. R. , III, R. L. Peters III, and E. B. Allen. 1988. Ecological restoration as a strategy for conserving biological diversity. Environmental Management 12:55-72.
Kauffman, J. B., R. L. Bescheta, N. Otting, and D. Lytjen. 1997. An ecological perspective of riparian and stream restoration in the Western United States. Fisheries 22:12-24.
Kentula, M. E., R. P. Brooks, S. E. Gwin, C. C. Holland, A. D. Sherman, and J. C. Sifneos. 1993. An Approach to improving Decision Making in Wetland Restoration and Creation. C. K. Smoley, Boca Raton, Florida.
Lewis, R. R. III. 1990. Wetlands restoration/creation/enhancement terminology: Suggestions for standardization. Pages 417-422 in J. A. Kusler and M. E. Kentula (eds.), Wetland Creation and Restoration: The Status of the Science. Island Press, Washington, D.C.
Louda, S. M. 1988. Insect pests and plant stresses as considerations for revegetation of disturbed ecosystems. Pages 51-67 in J. Cairns (ed.), Rehabilitation of damaged ecosystems. CRC Press, Boca Raton, Florida.
Middleton, B. 1999. Wetland restoration, flood pulsing, and disturbance dynamics. John Wiley & Sons, Inc., New York.
Mitsch, W. J. and J. G. Gosselink. 1993. Wetlands, 2nd edition. Van Nostrand Reinhold, New York.
National Research Council. 1992. Restoration of Aquatic Ecosystems: Science, Technology, and Public Policy. National Academy Press, Washington D.C.
Strader, R. W., C. Stewart, J. Wessman, and B. Ray. 1994. Bottomland Hardwood Reforestation Guidelines. U.S. Fish and Wildlife Service, Technical Report.
Streever, W. (ed.). 1999. An International Perspective on Wetland Rehabilitation. Kluwer Academic Publishers, Dordrecht, The Netherlands.
U. S. Environmental Protection Agency (EPA). 1990. Wetlands: Meeting the President’s Challenge. Washington, D. C.
Wilson, R.R., J. M. Oliver, D. J. Twedt, and W. B. Uihlein III. In press. Bottomland hardwood restoration in the Mississippi Alluvial Valley: Looking Past the trees to see the Forest. In L. Fredrickson, (ed.) Ecology and Management of Bottomland Hardwood Systems: The State of our Understanding. Memphis, Tennessee.
Return to STRP Wetland Restoration index page
For
further information about the Ramsar Convention on Wetlands, please contact
the Ramsar Convention Bureau, Rue Mauverney 28, CH-1196 Gland,
Switzerland (tel +41 22 999 0170, fax +41 22 999 0169, e-mail 
).
Posted 8 January 2001, updated 15 February 2002, Bill Streever and Dwight Peck.
